Space History for December 21

If you are not already a subscriber, you
are welcome to enter your email address here to sign up to receive the Space
History newsletter on a daily basis.Under no circumstances will we
release your legitimate email address entered here to outside persons or
organizations, and it will only be used for mailing the specific information you
have requested.

Enter your email address here:

Unsubscribe instructions are included in every newsletter issue in
case you decide you no longer wish to receive it.

Note: We record the IP address from which subscriptions
are entered to help prevent SPAM abuses.

Race To Space
Someone will win the prize...... but at what cost?
Visit RaceToSpaceProject.com
to find out more!

1966 10:19:00 GMTUSSR launched Luna 13 for a soft landing on the Moon.

The Luna 13 spacecraft was launched 21 December 1966 toward the Moon and accomplished a soft landing on 24 December 1966, in the region of Oceanus Procellarum. The petal encasement of the spacecraft opened, antennas were erected, and radio transmissions to Earth began four minutes after landing. On 25 December and 26 December 1966, the spacecraft television system transmitted panoramas of the nearby Lunar landscape at different Sun angles. Each panorama required approximately 100 minutes to transmit. The spacecraft was equipped with a mechanical soil-measuring penetrometer, a dynamograph, and a radiation densitometer for obtaining data on the mechanical and physical properties and the cosmic-ray reflectivity of the Lunar surface. Transmissions from the spacecraft apparently ceased before the end of December 1966.ref:nssdc.gsfc.nasa.gov

Apollo 8 was originally meant to be an Earth orbital test, like the Apollo 9 mission. However, it was becoming clear the Soviets were trying to preempt the first Lunar flyby with their Zond program, which aimed to fly a stripped down Soyuz on a Proton rocket carrying 1 or 2 cosmonauts to the Moon. The Soviets conducted a partially successful unmanned test in September 1968, which spurred NASA into redesignating the Apollo 8 mission on short notice. Apollo 8 was therefore moved up to be a Lunar flight. The Apollo 8 crew rode inside the Command Module, with no Lunar lander attached. They were the first astronauts to be launched by the Saturn V, which had flown only twice before.

Apollo 8 was launched 21 December 1968, crewed by Frank Borman, commander; Jim Lovell, Command Module pilot; William A. Anders, Lunar Module pilot (a misnomer, since there was no Lunar Module on the mission). Approximately two hours and fifty minutes after leaving the ground, the Saturn V's S-IVB third stage was restarted, propelling the crew from an Earth parking orbit velocity of 7792.8 meters per second to a translunar trajectory velocity of 10,822 meters per second. 66 hours 16 minutes later, on 24 December 1968, the Service Module engines were ignited to put Apollo 8 into orbit around the Moon.

As the spacecraft passed behind the Moon for the first time, and communications were interrupted, the Apollo 8 crew became the first humans to see the far side of the Moon. The next 12 hours of crew activity in Lunar orbit involved photography of both the near and far sides of the Moon and landing-area sightings. The crew completed photographic exercises in an excellent manner. Over 800 70 mm still photographs were obtained. Of these, 600 were good-quality reproductions of Lunar surface features, and the remainder were of the S-IVB during separation and venting, and long-distance Earth and Lunar photography. Over 700 feet of 16 mm film were also exposed during the S-IVB separation, Lunar landmark photography through the sextant, Lunar surface sequence photography, and documentation of intravehicular activity.

One of the most famous photos from this mission is the "Apollo 8 Earthrise View" (AS08-14-2383) where the Earth was about five degrees above the Lunar horizon in a telephoto view taken when the Apollo 8 spacecraft was near 110 degrees east longitude. The horizon, about 570 kilometers (350 statute miles) from the spacecraft, was near the eastern limb of the Moon as viewed from the Earth. The width of the view at the horizon was about 150 kilometers (95 statute miles). On the Earth, 240,000 statute miles away, the sunset terminator was crossing Africa. The crew took the photo around 10:40 a.m. (Houston time) on the morning of 24 December (approximately 15:40 GMT). In the picture, the South Pole is in the white area near the left end of the terminator, and North and South America are under the clouds.

The crew initially followed the Lunar orbit mission plan and performed all scheduled tasks. However, because of crew fatigue, the commander made the decision to cancel all activities during the final four hours in Lunar orbit to allow the crew to rest. The only activities during this period were a required platform alignment and preparation for transearth injection. A planned 26-minute 43-second television transmission of the Moon and Earth was made Christmas Eve, during which the crew read the first ten verses of Genesis from the Bible, then wished viewers "Good night, good luck, a Merry Christmas, and God bless all of you, all of you on the good Earth." An estimated one billion people in 64 countries heard or viewed the live reading and greeting; delayed broadcasts reached an additional 30 countries that same day.

After ten revolutions and 20 hours 10 minutes 13.0 seconds in Lunar orbit, the transearth injection maneuver was performed with the Service Propulsion System, and the astronauts were on their way home.

The Service Module was jettisoned as Apollo 8 approached Earth, and the Command Module followed an automatically guided entry profile. The Command Module reentered Earth's atmosphere (400,000 feet altitude) at a velocity of 36,221.1 ft/second following a transearth coast of 57 hours 23 minutes 32.5 seconds. The ionization became so bright during entry that the Command Module interior was bathed in a cold blue light as bright as daylight. At 180,000 feet, as expected, the lift of the Command Module bounced it to 210,000 feet, where it then resumed its downward course. The parachute system effected splashdown of the Command Module in the Pacific Ocean at 15:51:42 GMT (10:51:42 a.m. EST) on 27 December 1968. Mission duration was 147:00:42.0. The impact point was 1.4 nautical miles from the target point and 2.6 n mi from the recovery ship U.S.S. Yorktown.

Venera 12 was part of a two-spacecraft mission to study Venus and the interplanetary medium. Each of the two spacecraft, Venera 11 and Venera 12, consisted of a flight platform and a lander probe. Identical instruments were carried on both spacecraft. The flight platform had instruments to study solar wind composition, gamma ray bursts, ultraviolet radiation, and the electron density of the ionosphere of Venus. The lander probe carried instruments to study the characteristics and composition of the atmosphere of Venus.

Venera 12 was launched into a 177 x 205 km, 51.5 degree inclination Earth orbit, from which it was propelled into a 3.5 month Venus transfer orbit, which involved two mid-course corrections, on 21 September and 14 December. After ejecting the lander probe on 19 December, two days before encounter, the flight platform continued past Venus in a heliocentric orbit. The flight platform's near encounter with Venus occurred on 21 December 1978, at approximately 34,000 km from the planet. The flight platform acted as a data relay for the descent craft for 110 minutes until it flew out of range, then continued to return its own measurements on interplanetary space. The platform was equipped with a gamma ray spectrometer, retarding potential traps, UV grating monochromator, electron and proton spectrometers, gamma ray burst detectors, solar wind plasma detectors, and two-frequency transmitters.

The Venera 12 descent craft carried instruments designed to study the detailed chemical composition of the atmosphere, the nature of the clouds, and the thermal balance of the atmosphere. After separating from its flight platform on 19 December 1978, it entered the atmosphere of Venus two days later, at 11.2 km/sec (approximately 25,000 mph). During the descent, it employed aerodynamic braking, followed by parachute braking, and ending with atmospheric braking. It made a soft landing on the surface at 06:30 Moscow time on 21 December 1978 after a descent time of approximately 1 hour. The touchdown speed was 7-8 m/s (15-18 mph). Information was transmitted to the flight platform for relay to Earth until the flight platform moved out of range 110 minutes after the lander touchdown.

Both Venera 11 and 12 landers failed to return the planned color television views of the surface, and to perform soil analysis experiments. All of the camera protective covers failed to eject after landing (the cause was not established). Some US literature noted that the imaging system "failed" but did return some data. The soil drilling experiment was apparently damaged by a leak in the soil collection device, the interior of which was exposed to the high Venusian atmospheric pressure. The leak had probably formed during the descent phase because the lander was less aerodynamically stable than had been thought. Consequently, the landing gear of the following two landers (Venera 13 and 14) were equipped with tooth-shaped stabilizers.

Two other experiments on the lander also failed, and their failure was acknowledged by the Soviets at the time.

Among the instruments on board was a gas chromatograph to measure the composition of the Venus atmosphere, instruments to study scattered solar radiation and soil composition, and a device named Groza which was designed to measure atmospheric electrical discharges. Results reported included evidence of lightning and thunder, a high Ar36/Ar40 ratio, and the discovery of carbon monoxide at low altitudes.

The Venera 12 flight platform continued in solar orbit, and successfully used its Soviet-French ultraviolet spectrometer to study Comet Bradfield on 13 February 1980 (one year and two months after its Venus encounter). At that time, the spacecraft was 190,373,790 km from Earth.

The Vega mission combined a Venus swingby and a Comet Halley flyby by two identical spacecraft, Vega 1 and Vega 2, which were launched 15 December 1984 and 21 December 1984, respectively. After carrying Venus entry probes to the vicinity of Venus on 11 and 15 June 1985, respectively, the two spacecraft used Venus' gravity to get speed boosts to intercept Comet Halley. The first spacecraft encountered Comet Halley on 6 March 1986, and the second three days later. The flyby velocity was 77.7 km/s. Although the spacecraft could be targeted with a precision of 100 km, the position of the spacecraft relative to the comet nucleus was estimated to be known only to within a few thousand kilometers because of variations in the comet's orbit. This, together with the problem of dust protection, led to estimated flyby distances of 10,000 km for the first spacecraft and 3000 km for the second. Data were taken from 2.5 hours before through 0.5 hours after the closest approaches, with several periods of data taking before and after, each lasting about 2 hours.

The Venus instrumentation packages each consisted of a sphere 240 cm in diameter, which separated from the spacecraft bus two days before arrival at Venus and entered the planet's atmosphere on an inclined path, without active maneuvers, as was done on previous Venera missions. The lander probes (identical to those of Venera 9 through 14) had two objectives, the study of the atmosphere and the study of the superficial crust. In addition to temperature and pressure measuring instruments, the descent probes carried a UV spectrometer for measurement of minor atmospheric constituents, an instrument dedicated to measurement of the concentration of H2O, and other instruments for determination of the chemical composition of the condensed phase: a gas-phase chromatograph; an X-ray spectrometer observing the fluorescence of grains or drops; and a mass spectrograph measuring the chemical composition of the grains or drops. The X-ray spectrometer separated the grains according to their sizes using a laser imaging device, while the mass spectrograph separated them according to their sizes using an aerodynamical inertial separator. A toroidal system similar to that on Veneras 13 and 14 was designed to absorb shock on landing. After landing, a small surface sample near the probe was to be analyzed by gamma spectroscopy and X-ray fluorescence. The UV spectrometer, the mass spectrograph, and the pressure- and temperature-measuring instruments were developed in cooperation between French and Soviet investigators.

After separation, the Vega 1 lander entered the Venus atmosphere on 11 June 1985 at 01:59:49 UT at 10.75 km/s with an entry angle of 18.23 degrees. The pilot parachute was deployed at 02:00:27 UT at an altitude of 65 km and the braking parachute opened 11 seconds later at 64.5 km. The upper heat protection hemisphere was released at that time and the lower hemisphere 4 seconds later at 64.2 km. The upper hemisphere contained the deployment system for the balloon aerostat. The parachute was released at 02:09:37 at 47 km, after which the lander used aerobraking to descend through the thick Venus atmosphere, with drag devices minimizing vibrations and spin and providing stability. At an altitude of 18 km a mechanical shock of unknown origin (possibly due to a jammed valve in an upper compartment suddenly releasing) triggered a ground-contact accelerometer which caused early deployment of the soil drill of the X-ray flourescence spectrometer. The drill was rendered unusable at landing due to the premature deployment. The lander touched down at 03:02:54 UT on 11 June 1985 at 7.5 N, 177.7 E, just north of eastern Aphrodite Terra. The altitude of the touchdown site was 0.6 km below the planetary mean radius, the measured pressure at the landing site was 95 atm and the temperature was 740 K.

After separation, the Vega 2 lander entered the Venus atmosphere on 15 June 1985 at 01:59:30 UT at 10.80 km/s with an entry angle of 19.08 degrees. The pilot parachute was deployed at 02:00:05 UT at an altitude of 65 km and the braking parachute opened 11 seconds later at 64.5 km. The upper heat protection hemisphere was released at that time and the lower hemisphere 4 seconds later at 64.2 km. The upper hemisphere contained the deployment system for the balloon aerostat. The parachute was released at 02:09:15 at 47 km, after which the lander used aerobraking while descending through the thick Venus atmosphere, with drag devices minimizing vibrations and spin and providing stability. The lander touched down at 03:00:50 UT on 15 June 1985 at 8.5 S, 164.5 E, in eastern Aphrodite Terra. The altitude of the touchdown site was 0.1 km above the planetary mean radius, and the measured pressure and temperature at the landing site were 91 atm and 736 K. The surface sample was found to be an anorthosite-troctolite.

In addition to the lander probes, constant-pressure instrumented balloon aerostats were deployed immediately after entry into the atmosphere at an altitude of 54 km. Each 3.4 meter diameter balloon supported a total mass of 25 kg, including a 5 kg payload that hung suspended 12 meters below the balloon. It floated at approximately 50 km altitude in the middle, most active layer of the Venus three-tiered cloud system. Data from the balloon instruments were transmitted directly to Earth for the lifetime of the mission. Onboard instruments were to measure temperature, pressure, vertical wind velocity, and visibility (density of local aerosols). Very long baseline interferometry was used to track the motion of the balloon to provide the wind velocity in the clouds. Tracking was done by a 6 station network on Soviet territory and by a network of 12 stations distributed world-wide (organized by France and the NASA Deep Space Network). The balloons measured downward gusts of 1 meter/s and showed horizontal wind velocities up to 240 km/hr. After two days and 9000 km, the balloons entered the dayside of Venus where they expanded and burst due to solar heating.

1988 09:57:00 GMTUSSR cosmonauts Vladimir Titov and Musa Manarov returned to Earth with French astronaut Jean-Loup Chretien aboard Soyuz TM-6 after Titov and Manarov had spent a year in space on the Mir space station.

USSR launched Soyuz TM-6 on 29 August 1988, which transported to the Mir orbital station a Soviet-Afghan crew comprised of cosmonauts V. A. Lyakhov, V. V. Polyakov and A. A. Momand (Afghanistan) to conduct joint research and experiments with cosmonauts V. G. Titov and M. K. Manarov who were already aboard Mir.

Soyuz TM-6 returned from Mir on 21 December 1988 with cosmonauts Titov, Manarov and Chretien aboard.ref:nssdc.gsfc.nasa.gov

STS 103 was launched 19 December 1999 for eight days in orbit on a mission to service the Hubble Space Telescope. Two teams of space walkers spent more than 24 hours conducting extravehicular activities (EVAs) installing new equipment and performing other maintenance tasks to upgrade the space-based observatory.

The Hubble Telescope was captured 21 December 1999. Mike Foale, John Grunsfeld, Claude Nicollier and Steve Smith performed 3 EVAs, each just over 8 hours long, on 22 December, 23 December and 24 December. The new, improved, and upgraded equipment included six fresh gyroscopes, six battery voltage/temperature improvement kits, a faster and more powerful main computer, a next-generation solid state data recorder, a new transmitter, an enhanced fine guidance sensor, and new insulation. Hubble was released back into its own orbit on 25 December 1999.

The STS 103 mission ended when Discovery landed at Kennedy Space Center, Florida on 27 December 1999, approximately 49 minutes less than 8 days after it was launched, and having traveled 3.25 million miles.